Virtual TapeServer 6.04.04 for NonStop Servers Release Notes
Resolved Issues and Enhancements | 12
data to a disk array that has a small number of drives in the disk group or with FC
attached ATA (FATA) drives. This fix removes the change made in 6.04.01 for the 6.04.04
release, allowing the VTS operating system to again determine when to flush the VTS file
system cache. (TL-4595, EAR 6294, EAR 5916)
SCSI negotiated speed output was logged to the console every 5 seconds. This
issue was introduced in 6.04.03.01. Now, the negotiated SCSI speed is logged to the
console (and kern_messages) only when the negotiation speed changes. (TL-4557, EAR
6540, EAR 6590)
Could not unmount a tape if a VTD was reserved by the host. Previously, if a VTD
was reserved by a host, the user was unable to unmount the tape in order to mount a new
one. Now, the user can mount and unmount tapes manually as needed while the host still
holds the reservation. (TL-4770, EAR 6643, EAR 6807)
Malformed error for auto-generated HP LTO 3 drive. Previously, a “database entry
for id page malformed” error may have been generated for an auto-generated HP LTO3
emulated tape drive type. This has been was fixed. (TL-4713, EAR 6630)
Warning now sent to host server before space is exhausted. When VAULT space is
exhausted, attempting to write to virtual tapes now results in an end of tape message sent
to the host while allowing writes to space already consumed by the virtual tape. (TL-4168)
Tape write buffering is now enabled. Tape write buffering has been added to improve
performance. This feature is enabled by default. 134MB of allocated shared memory is
provided to support a queue depth of 4 (256K writes). (TL-4127)
Four parameters can be added to vts.conf to change the default behavior:
engine_MultiStreamYield - Defines the number of events that can occur before VTS forces
a sched_yield(). Values: 1 to 20,000. 0 disables this feature.
engine_TapeWriteCmdDepth - Defines the number of write commands that will be
responded to (buffered) without writing the data to disk. Values: 1 to 3.
engine_TapeWriteStateTimeout - Sets the timeout value in milliseconds that is compared
to the time between commands. If a new WRITE command comes in while VTS is idle and
the previous command occurred longer ago than this value, the state is reset to IDLE so
that the unit attention can be picked up (write buffering does not occur). Values: greater
than 0. 32-bit signed integer.
engine_DisableTapeWriteBuffering - Disables tape write buffering. Values: YES and NO.
Defaults:
engine_MultiStreamYield =2000 events
engine_TapeWriteCmdDepth=3 cmds
engine_TapeWriteStateTimeout=200mS
engine_DisableTapeWriteBuffering="NO"
Inconsistent information was sent to host about media type. When a host
requested information, including the media type in use, from VTS, different responses
were issued depending on whether the tape was loaded. Also, the type given may not have
been one that was applicable for that tape type. This has been fixed. (TL-4152, EAR 6222)
Serial number could be autogenerated to include a single digit. Serial numbers
could be autogenerated as single digits, which may not have been acceptable to host
systems. The autogenerated serial numbers were based on the BTLI of the drive. Now, the
serial number includes at least six digits; the last digits are the BTLI. (TL-3946)
vtsa user could not issue mount command. From the command line, the vtsa user
could not issue the /bin/mount command. This has been fixed. (TL-3981)